Missing for the last twenty years: the case of the southernmost populations of the Tropical Mockingbird Mimus gilvus (Passeriformes: Mimidae)
ZANON, M. S.; VALE, M. M.; ALVES, M. A. S.
Zoologia, v. 32, p. 01-08, 2015
DOI: http://dx.doi.org/10.1590/S1984-46702015000100001
Brazil; conservation status; IUCN; restinga; Rio de Janeiro,
The Tropical Mockingbird Mimus gilvus (Vieillot, 1808) is a widespread species in the Neotropics, but its southernmost populations in Brazil are ecologically (and possibly taxonomically) distinct, occurring only along the coast in restinga vegetation. Once considered the most common bird in restinga, it is becoming increasingly rare, likely due to habitat loss and illegal capture of nestlings. We conducted field surveys to provide an up-to-date distribution of the Tropical Mockingbird in the southernmost portion of the species’ range, in the state of Rio de Janeiro, supplying an estimate of its current regional population size and conservation status. We surveyed 21 restinga remnants in Rio de Janeiro, covering all major restinga areas in the state. For sites where the species’ presence was confirmed through transect line surveys, we estimated the local population size. The species was found at only four sites. The mean local population density was 52 individuals per km-2. The estimated current and historical Extent of Occurrence (EOO) were 256 km2 and 653 km2, respectively. Combining the population size and EOO results, we estimated that the population of the state of Rio de Janeiro currently ranges from 2,662 to 13,312 individuals, corresponding to an estimated reduction of 61% to 92% in population size in the last 20 years. The species, therefore, can be considered “Endangered” in the state of Rio de Janeiro. We recommend that a taxonomic study of the southernmost populations is carried out in order to clarify whether they represent a different, likely threatened species. We also recommend that the environmental regulations that protect restingas are used towards the protection of these populations.
The reduced effectiveness of protected areas under climate change threatens Atlantic forest tiger moths
FERRO, V. G.; LEMES, P.; MELO, A. S.; LOYOLA, R.
PLoS ONE, v. 9(9):e107792, 2014
Brock Fenton, University of Western Ontario, Canada
doi.org/10.1371/journal.pone.0107792
Conservation science; Climate change; Moths and butterflies; Forests; Species diversity; Biodiversity; Ecosystems; Ecological niches,
Climate change leads to species’ range shifts, which may end up reducing the effectiveness of protected areas. These deleterious changes in biodiversity may become amplified if they include functionally important species, such as herbivores or pollinators. We evaluated how effective protected areas in the Brazilian Atlantic Forest are in maintaining the diversity of tiger moths (Arctiinae) under climate change. Specifically, we assessed whether protected areas will gain or lose species under climate change and mapped their locations in the Atlantic Forest, in order to assess potential spatial patterns of protected areas that will gain or lose species richness. Comparisons were completed using modeled species occurrence data based on the current and projected climate in 2080. We also built a null model for random allocation of protected areas to identify where reductions in species richness will be more severe than expected. We employed several modern techniques for modeling species’ distributions and summarized results using ensembles of models. Our models indicate areas of high species richness in the central and southern regions of the Atlantic Forest both for now and the future. However, we estimate that in 2080 these regions should become climatically unsuitable, decreasing the species’ distribution area. Around 4% of species were predicted to become extinct, some of them being endemic to the biome. Estimates of species turnover from current to future climate tended to be high, but these findings are dependent on modeling methods. Our most important results show that only a few protected areas in the southern region of the biome would gain species. Protected areas in semideciduous forests in the western region of the biome would lose more species than expected by the null model employed. Hence, current protected areas are worse off, than just randomly selected areas, at protecting species in the future.
Multi-Scales Analysis of Primate Diversity and Protected Areas at a Megadiverse Region
PINTO, M. P.; SILVA JUNIOR, J. S. E.; ALMEIDA, A.; GRELLE, C. E. V.
Plos One, v. 9, p. e105205, 2014
https://doi.org/10.1371/journal.pone.0105205
Primates; Conservation science; Biodiversity; Conservation biology; Ecosystems; Mammals; Phylogeography; Forests,
In this paper, we address the question of what proportion of biodiversity is represented within protected areas. We assessed the effectiveness of different protected area types at multiple scales in representing primate biodiversity in the Brazilian Legal Amazon. We used point locality data and distribution data for primate species within 1°, 0.5°, and 0.25° spatial resolution grids, and computed the area of reserves within each cell. Four different approaches were used – no reserves (A), exclusively strict use reserves (B), strict and sustainable use reserves (C), and strict and sustainable use reserves and indigenous lands (D). We used the complementarity concept to select reserve networks. The proportions of cells that were classified as reserves at a grid resolution of 1° were 37%, 64%, and 88% for approaches B, C and D, respectively. Our comparison of these approaches clearly showed the effect of an increase in area on species representation. Representation was consistently higher at coarser resolutions, indicating the effect of grain size. The high number of irreplaceable cells for selected networks identified based on approach A could be attributed to the use of point locality occurrence data. Although the limited number of point occurrences for some species may have been due to a Wallacean shortfall, in some cases it may also be the result of an actual restricted geographic distribution. The existing reserve system cannot be ignored, as it has an established structure, legal protection status, and societal recognition, and undoubtedly represents important elements of biodiversity. However, we found that strict use reserves (which are exclusively dedicated to biodiversity conservation) did not effectively represent primate species. This finding may be related to historical criteria for selecting reserves based on political, economic, or social motives.
Mudanças climáticas e prioridades para a conservação da biodiversidade
LEMES, P.; LOYOLA, R.
Revista de Biologia Neotropical, v. 11(1), p. 47–57, 2014
UFG
doi.org/10.5216/rbn.v11i1.30699
priorização espacial; mudanças climáticas; diversidade filogenética; diversidade funcional; Mata Atlântica,
Processos globais como a perda de habitat, superexploração de recursos naturais, invasão biológica e mudanças climáticas estão conduzindo muitas espécies à extinção. Nesse cenário de alto risco de extinção, qual deve ser o critério para determinar prioridades de conservação? O que, onde e como proteger a biodiversidade? A resposta não é simples. Entre os efeitos esperados das mudanças climáticas, pode-se incluir o deslocamento das espécies para um espaço climático mais favorável, até mesmo fora de uma unidade de conservação. No entanto, eleger prioridades para a conservação da biodiversidade implica ir além das espécies, fazendo-se necessário a inclusão da história evolutiva e da manutenção dos processos nas comunidades. Aqui, apresentamos um panorama sobre os efeitos das mudanças climáticas sobre biodiversidade e como incluí-los em estudos de priorização espacial para a conservação. Ressaltamos a importância da conservação de anfíbios da Mata Atlântica, grupo mais ameaçado de extinção entre os vertebrados e, finalmente, apresentamos e discutimos estratégias de conservação consideram mais que a riqueza de espécies, incluindo também informações sobre a diversidade filogenética e funcional.
Possible impacts of climate change on wetlands and its biota in the Brazilian Amazon
Barros, D. F.; A. L. M. Albernaz
Brazilian Journal of Biology, v. 74, n. 4, p. 810-820, 2014
dx.doi.org/10.1590/1519-6984.04013
global warming; wetlands; mangrove; floodplains; Amazonia,
Wetlands cover approximately 6% of the Earth’s surface. They are frequently found at the interface between terrestrial and aquatic ecosystems and are strongly dependent on the water cycle. For this reason, wetlands are extremely vulnerable to the effects of climate change. Mangroves and floodplain ecosystems are some of the most important environments for the Amazonian population, as a source of proteins and income, and are thus the types of wetlands chosen for this review. Some of the main consequences that can be predicted from climate change for wetlands are modifications in hydrological regimes, which can cause intense droughts or inundations. A possible reduction in rainfall can cause a decrease of the areas of mangroves and floodplains, with a consequent decline in their species numbers. Conversely, an increase in rainfall would probably cause the substitution of plant species, which would not be able to survive under new conditions for a long period. An elevation in water temperature on the floodplains would cause an increase in frequency and duration of hypoxic or anoxic episodes, which might further lead to a reduction in growth rates or the reproductive success of many species. In mangroves, an increase in water temperature would influence the sea level, causing losses of these environments through coastal erosion processes. Therefore, climate change will likely cause the loss of, or reduction in, Amazonian wetlands and will challenge the adaptability of species, composition and distribution, which will probably have consequences for the human population that depend on them.
Have old species reached most environmentally suitable areas? A case study with South American phyllostomid bats
WEBER, M.; STEVENS, R.; LORINI, M. L; GRELLE, C. E. V.
Global Ecology and Biogeography (Print), v. 23, p. 1177-1185, 2014
10.1111/geb.12198
Age–area model; ecological niche modelling; environmental suitability; potential range; stasis post-expansion model; taxon cycle model; unfilled range,
Aim
We used ecological niche modelling to test different models explaining the lineage age–area relationship. We hypothesized that lineage age should influence the proportion of potential range unfilled by phyllostomid bat species. We made explicit predictions about possible relationships between the proportion of unfilled potential range and lineage age. Our goal was to analyse empirical data and fit the model that best describes our data.
Location
South America.
Methods
We modelled the ecological niche of 49 phyllostomid bat species using Maxent and Support Vector Machine (SVM). We calculated the proportion of unfilled potential range as the amount of area outside the current distribution divided by the current distribution (realized range size). Using a dated phylogeny, we regressed the proportion of unfilled potential range on lineage age. To compare our predictions we also regressed realized range size on lineage age.
Results
Unfilled potential range was weakly associated with lineage age. This relationship was an inverse function of lineage age, explaining between 0 and 17% of the proportion of unfilled potential range. Furthermore, the relationship between realized range size and lineage age exhibited a logarithmic function, with lineage age explaining between 13 and 20% of the variation in realized range size.
Main conclusions
Different regression models indicated that old phyllostomid species have smaller unfilled ranges than young species. That is, old species have filled most of the areas that are suitable for them. Furthermore, old species have larger realized ranges than young species. We thus refuted both the lineage age–area and taxon cycle models and lent support to the stasis post-expansion model. This suggests that bat species can reach most of their potential range rapidly after cladogenesis and such occupation remains more or less constant through time.
Climate change threatens protected areas of the Atlantic Forest
LEMES, P.; MELO, A. S.; LOYOLA, R. D.
Biodiversity and Conservation, v. 23(2), p. 357–368, 2014
10.1007/s10531-013-0605-2
Amphibians; Dispersal; Ecological niche models; Global warming; Reserve network,
Only 7 % of the Atlantic Forest Biodiversity Hotspot is currently protected, though it holds 18 % of all amphibian species in South America. How effective would the Atlantic Forest network of protected areas (PAs) be in a changing climate? Are there some intrinsic features of PAs that drive species loss or gain inside them? We addressed these questions by modeling the ecological niches of 430 amphibian species in the Atlantic Forest and projecting their distributions into three future climate change simulations. We then assessed changes in species richness inside PAs for different time frames and tested their significance via null model. The number of species should decline within Atlantic Forest network of PAs under changing climate conditions. Only altitude was a good predictor of species gains or lost inside PAs. Therefore, we suggest that new PAs established in highlands would be more effective to alleviate the effects of climate change on this imperiled fauna.
Clade-specific consequences of climate change to amphibians in Atlantic Forest protected areas
LOYOLA, R. D.; LEMES, P.; BRUM, F. T.; PROVETE, D. B.; DUARTE, L. D. S.
Ecography, v. 37, p. 65–72, 2014
10.1111/j.1600-0587.2013.00396.x
The rapid global decline of amphibian population is alarming because many occur for apparently unknown or enigmatic reasons, even inside protected areas (PAs). Some studies have predicted the effects of climate change on amphibians’ distribution and extinction, but the relationship and consequences of climate change to the phylogenetic structure of amphibian assemblages remain obscure. By applying robust techniques for ecological niche modeling and a cutting-edge approach on community phylogenetics, here, we evaluate how climate change affects the geographical pattern of amphibian species richness and phylogenetic diversity in the Atlantic Forest Biodiversity Hotspot, Brazil, as well as how the phylogenetic composition of amphibian assemblages respond to climate change. We found that most species contracted their ranges and that such responses are clade specific. Basal amphibian clades (e.g. Gymnophiona and Pipidae) were positively affected by climate change, whereas late-divergent clades (e.g. Cycloramphidae, Centrolenidae, Eleutherodactylidae, Microhylidae) were severely impacted. Identifying major changes in the phylogenetic pool represents a first step towards a better understanding of how assembly processes related to climate change will affect ecological communities. A deep analysis of the impacts of climate change not only on species, but also on the evolutionary relationships among species might foster the discussion on clade-level conservation priorities for this imperiled fauna.